Note that the employed controller requires knowledge of the agent and object dynamics. In case of dynamic parameter uncertainty, standard adaptive control schemes that attempt to estimate potential uncertainties in the model (e.g., [1]}, [2]}) would intrinsically create internal forces, since the dynamics of the system would not be accurately compensated. The same holds for schemes that employ force/torque sensors that provide the respective measurements at the grasp points (e.g., [3]}, [4]}) in periodic time instants. Since the interaction forces depend explicitly on the control input, such measurements will unavoidably correspond to the interaction forces of the previous time instants due to causality reasons, creating thus small disturbances in the dynamic model.
